Diethyl Sulfate → HCID 23042369, compound

Participants

Reaction Steps

4.5 g of cyclopentyl 2-chloro-5-[3.6-dihydro-2,6-dioxo-4-trifluoromethyl-1(2H)-pyrimidinyl]-4-fluorobenzoate, 2.1 g of potassium bicarbonate and 1.5 ml of diethyl sulphate are heated at reflux temperature in 50 ml of acetone for 4 hours. Subsequently. the solvent is distilled off and the residue is partitioned in 150 ml of diethyl ether and 150 ml of water. The aqueous phase is extracted with a further 150 ml of diethyl ether and the combined organic phases are washed twice with 150 ml of water each time, dried over anhydrous magnesium sulphate and concentrated. The residue is purified by chromatography on a silica gel column using ethyl acetate/n-hexane (1:4) as the eluent. In this manner there are obtained cyclopentyl 2-chloro-5-[3-ethyl-3,6-dihydro-2,6-dioxo-4-trifluoromethyl-1(2H)-pyrimidinyl]-4-fluorobenzoate as a colourless oil, 1H-NMR (CDCl 3, 400 MHz : 1 36 (t3H), 1.56-2.04 (m,8H), 4.02 (q,2H), 5.36-5.45 (m,1H), 6.35 (s,1H), 7.36 (d,1H), 7.82 (d,1H); mass spectrum (m/e): M+ 448 (1), as well as cyclopentyl 2-chloro- 5-[2-ethoxy-6-oxo-4-trifluoromethyl-1(6H)-pyrimidinyl]-4-fluorobenzoate, m.p. 90°-91° C.

Provenance & Evidence